In U.S. Pat. No. 5,169,441, Lauzon suggests the use of Zeta Potential for characterizing particulates such as pigments treated with cationic polymers. Lauzon's U.S. Pat. 5,846,308 describes the stabilization of a rosin dispersion for use as a sizing composition by treating it with a “cationic colloidal coacervate” which may include both a cationic polymer and an anionic surfactant; the finished sizing composition is to have a Zeta Potential of at least 20 millivolts. Poly(diallyldimethyl ammonium chloride), sometimes known as polyDADMAC, is the preferred cationic polymer. Also, Lauzon's U.S. Pat. No. 6,315,824 describes a similar coacervate stabilizing system used for hydrophobic non-rosin sizing agents, which may be liquid as well as solid. See also Lauzon's U.S. Pat. No. 4,507,210, which suggests a correlation of Zeta Potential to certain filtration properties in the treatment of shale and clay in hydrocarbon recovery; see also Engelmann et al in U.S. Pat. No. 5,196,401.
Other compositions comprising a cationic polymer and an anionic surfactant, often in high ratios of anionic surfactant to cationic polymer, may be found in Matz and LeMar U.S. Pat. No. 6,110,451, Verdicchio and Spilatro U.S. Pat. No. 4,948,576, and the shampoo and other personal care products described by Guskey et al in U.S. Pat. Nos. 6,297,203 and 6,221,817, Sako et al in U.S. Pat. No. 6,284,230, (which also describes betaines) Hoshowski et al in U.S. Pat. No. 5,137,715, and Snyder et al in U.S. Pat. No. 6,248,317.
Combinations of cationic polymers, betaines, and anionic surfactants may be inferred from the numerous combinations of materials that are possibly viscoelastic within the disclosure of Balzer in U.S. Pat. No. 5,956,502, dealing with compositions for use on the hair and skin. See also the combination of cationic polymer with anionic surfactants for use as an automatic dishwashing detergent, in Tartakovsky et al U.S. Pat. No. 6,281,180.
In the field of hydrocarbon recovery from the earth, formation fracturing fluids proposed by Zhang in Canadian patent 2,257,699 combine anionic surfactants such as sodium xylene sulfonate and cationic surfactants such as N, N, N, trimethyl-1-octadecammonium chloride to make a gel said to be viscoelastic. Carbon dioxide is added to similar combinations in Zhang's Canadian patent 2,257,697 to generate a foam. Borchardt et al, in U.S. Pat. No. 4,409,110, describe formation flooding compositions which may comprise cationic polymers and anionic surfactants. Numerous combinations of surfactants and other compounds are proposed by Dahayanake et al in U.S. Pat. No. 6,258,859 (WO 98/56497; PCT/US/12067). See also the compositions said to be viscoelastic and proposed for well treatment by Hughes et al in U.S. Pat. No. 6,232,274 and Jones et al in U.S. Pat. No. 6,194,356.
Also in the art of producing oil and gas from underground formations, it is known to add friction reducing compositions to the fracturing fluids, to conserve energy. As summarized in Persinski et al U.S. Pat. No. 3,768,565, “it is necessary to inject sufficient amounts of fracturing fluids . . . in order to effectuate cracks or fractures in the subterranean formation. Pressures as high as 3000 to 10000 psi measured at the surface are often required. Because of the large quantities of fluid needed, the high velocities required, and the general irregularities of the formation, it is difficult to obtain satisfactory results in many fracturing operations because of the energy loss.” Column 1, lines 44–55. See also column 1, lines 14–32: “It is well known that in the movement of aqueous fluids through conduits, friction is encountered and hence energy is lost. This energy loss is apparent from the pressure drop obtained in moving the fluid through a given distance and is directly proportional to the velocity of the fluid. According to the well-known laws of fluid dynamics, as long as the critical Reynolds Number of a fluid medium flowing through a conduit is not exceeded, the fluid moves in laminae which are actually aligned along the conduit. Under these conditions of laminar flow, the energy loss is minimal. However, when the velocity is greatly increased, the critical Reynolds Number is exceeded and turbulence occurs. This turbulence represents the change from laminar to nonlaminar flow. In addition, turbulence is increased by any irregularities in the conduit or in the entering or exiting formation which will distort the flow pattern. An increase in turbulence causes an increase in the amount of energy lost through friction.” Since these summaries were written in 1971, oil and gas production conditions and demands have further heightened the requirements for friction reducing additives for fracturing fluids. Various water-soluble polymers are suggested for friction reducing in the Persinski patent as well as several others cited in it. The reader may also be interested in the polymers used by Boothe et al in U.S. Pat. No. 3,868,328, Martin et al U.S. Pat. No. 3,943,060, Gayley et al U.S. Pat. No. 3,562,226, McClaflin et al U.S. Pat. No. 3,730,275, Griffin U.S. Pat. No. 4,153,066, McDonald et al U.S. Pat. No. 4,182,417, Teot et al U.S. Pat. No. 4,615,825, Karl U.S. Pat. No. 4,637,418, and Seheult et al U.S. Pat. No. 4,717,488.
Many of the materials used in the past for friction reduction require economically unattractive concentrations. Others are unattractive for various purposes because of their chemical reactivity. There remains a need for friction reducing materials which may be used at lower concentrations.